package benworks.bookcode.jvm.chapter3;

public class FinalizeEscapeGC {

	public static FinalizeEscapeGC SAVE_HOOK = null;
	
	public void isAlive(){
		System.out.println("yes, i am still alive:);");
		
	}
	
	@Override
	protected void finalize() throws Throwable {
		super.finalize();
		System.out.println("finalize method executed!!");
		FinalizeEscapeGC.SAVE_HOOK = this;
	}
	
	public static void main(String[] args) throws InterruptedException {
		SAVE_HOOK = new FinalizeEscapeGC();
		
		//对象第一次成功拯救自己；
		SAVE_HOOK = null;
		System.gc();
		
		//因为finalizer方法优先级很低，暂停0.5秒，以等待。
		Thread.sleep(500);
		
		if (SAVE_HOOK !=null) {
			SAVE_HOOK.isAlive();
		}else {
			System.out.println("no, i am dead!:(");
		}
		
		//下面这段代码与上面完全相同，但这次自救却失败了
		SAVE_HOOK = null;
		System.gc();
		
		//因为finalizer方法优先级很低，暂停0.5秒，以等待。
		Thread.sleep(500);
		
		if (SAVE_HOOK !=null) {
			SAVE_HOOK.isAlive();
		}else {
			System.out.println("no, i am dead!:(");
		}	
	}
}
